I am not trying to miss-lead anyone, just stating what is working for me.
If I run into trouble, I have no problem getting in there and fixing it...
The oil that I am putting in there is filtered 2 times before going into the tank. The last filter I changed had about 4 months worth of #2 and about 120 +/- gallons of WVO mix. Pulled the filter and it was spotless, about 4 guys in the local coffee night group witnessed this also. However, NONE of them are running WVO. One guy this past weekend wanted to try it. He was from Virginia and had to drive back home from CT. I advised him NOT TO DO IT!